Get the sourced code for 6.6 kernel: git clone https://github.com/minuscat/rpi-6.6.y.git
Go into kernel directory: cd rpi-6.6.y/
Review the url on building rpi kernels
Set the KERNEL environment variable to a unique value (this is just an example): KERNEL=kernel_2712_l4s
Make a Rpi5 config: make bcm2712_defconfig
Set prague CCA & dual queue kernel flags: make menuconfig
- Networking support > Networking options > TCP: advanced congestion control: tcp prague
- Networking support > Networking options > QoS and/or fair queueing: Dual queue
Set CONFIG_LOCALVERSION environment variable to a unique value: CONFIG_LOCALVERSION="-l4s-kernel"
Compile kernel, modules, device tree blobs: make -j6 Image.gz modules dtbs
Install modules: make -j6 modules_install
rjmcmahon@raspberrypi:~ $ cd /usr/local/src
rjmcmahon@raspberrypi:/usr/local/src $ su
git clone https://github.com/google/bbr.git
Checkout l4s branch
cd bbr
git checkout l4s-testing-2023-02-23-v3
Download bcm2711_defconfig from this site
copy into .config
copy into arch/arm64/configs/bcm2711_defconfig (optional)
make menuconfig
check platform as Broadcom BCM2835 family
Verify Networking support > Networking options > TCP: advanced congestion control
make -j4 Image modules
wait awhile (like at 87 minutes)
Install custom kernel
make modules_install
make install
emacs /boot/config.txt
kernel=vmlinuz-5.15.72-v8+
# uncomment if you get no picture on HDMI for a default "safe" mode
#hdmi_safe=1
or sudo systemctl set-default multi-user.target
reboot
Verify TCP Prague and BBRv2
Uname -r
rjmcmahon@raspberrypi:~ $ uname -r
5.15.72-v8+
systctl -a | grep avail
rjmcmahon@raspberrypi:~ $ sudo sysctl -a | grep avail
kernel.random.entropy_avail = 256
kernel.seccomp.actions_avail = kill_process kill_thread trap errno user_notif trace log allow
net.ipv4.tcp_available_congestion_control = reno bbr bbr2 cubic dctcp vegas prague
net.ipv4.tcp_available_ulp =
Configuration
for Testing
You
can configure the test machine with the following commands.
Enabling Accurate ECN
sysctl net.ipv4.tcp_ecn=3
Enabling BBRv2 CC w/ Accurate ECN
sysctl net.ipv4.tcp_ecn=3 net.ipv4.tcp_congestion_control=bbr2
Enabling TCP Prague CC w/ Accurate ECN
sysctl net.ipv4.tcp_ecn=3 net.ipv4.tcp_congestion_control=prague
Enabling CUBIC CC w/ Accurate ECN
sysctl net.ipv4.tcp_ecn=3 net.ipv4.tcp_congestion_control=cubic
Enabling CUBIC CC w/o Accurate ECN
sysctl net.ipv4.tcp_ecn= net.ipv4.tcp_congestion_control=cubic
Build the latest iperf 2
cd /usr/local/src
git clone https://git.code.sf.net/p/iperf2/code iperf2-code
cd iperf2-code
.configure
make -j 4
make install
Build goresponsiveness tool (git repo)
wget https://go.dev/dl/go1.20.6.linux-arm64.tar.gz
tar -C /usr/local/ -xvf go1.20.6.linux-arm64.tar.gz
tar -C /usr/local -xzf go1.20.6.linux-arm64.tar.gz
export PATH=$PATH:/usr/local/go/bit
type go
go version
cd goresponsiveness/
go mod download
go build networkQuality.go
TCP client stats
Iperf 2 TCP CCA up stream
Adding a realtime clock
Example clone with dd (from micro SD to file, use lsblk to find device)
[rjmcmahon@ryzen3950 L4S]$ sudo dd bs=4M if=/dev/sdc of=l4s_kernel conv=fsync
[sudo] password for rjmcmahon:
15226+1 records in
15226+1 records out
63864569856 bytes (64 GB, 59 GiB) copied, 692.6 s, 92.2 MB/s
Example clone with dd (from file to micro SD, use lsblk to find device)
Cross compile for a buildroot small embedded system (not done)
Testing Notes
Wi-Fi Low Latency Table
A
picture
